NF - Mercury 115HP with Command Thrust or 150 HP

[hutch4113]

Based on the cost to repair my motor, it appears to make more sense to get a new one.  I have have contemplated upgrading before.  Because my boat has a Merc - I will probably stick with it, as it is already wired, etc. for that brand.

I may also go 4 Stroke (currently have a 115HP Optimax).  

I am doing some research on the 115HP with Command Thrust (4 Stroke) or just going to max HP and hang a 150 on is (that is the max rating for my boat).

Anyone have experience with either motor?  Boat is 18.2 feet -  Aluminum.  Would be interested to know what performance you are seeing, etc.  

[AKRISONER]

i would not recommend switching to a similar HP 4 stroke if you were already considering moving up in power with your 2 stroke 115. 

to move an 18 foot aluminum, i would highly suggest going 150 if you are going 4 stroke. put it this way...that 4 stroke 115 would feel a lot like a 80hp 2 stroke

[BillM]

MAX rating every single time.

[OhioFisherman]

A 150 hp in most if not all cases will run away from a 115 hp, if your boat is rated for a 150 a 115 seems a bit under powered? better to solve than now than later?

[hutch4113]

33 minutes ago, OhioFisherman said:

A 150 hp in most if not all cases will run away from a 115 hp, if your boat is rated for a 150 a 115 seems a bit under powered? better to solve than now than later?

Actually power has been good, once I got it propped properly.  With two people can get 40+ MPH out of it.  I just don't have experience with the new 4 Stroke Motors.  It appears that the new ones don't have the power/weight issues that old 4 Strokes had.

[AKRISONER]

heres a real life example...I have two boats up at our place.

18 foot aluminum with a 2017 4 stroke 150 vs fibreglass 17 with 1998 two stroke 130...its not even close...the 130 absolutely crushes the 150 every single time hole shot, top end, acceleration, everything.

I still love the 4 stroke, it sips gas, doesnt need oil, cruises at lower speeds much better like a car...but its also got enough power. I wouldnt want to drive the thing with a 115 on it.

 

Edited July 9, 2018 by AKRISONER

[Terry]

It is hard to compare as hull design is the biggest factor on performance

[BillM]

Yeah you really can't compare those two boats, lol.    Apples/oranges.   Although if you're getting 40+mph out of that boat as it sits, is there any reason you need more speed then that?   Sounds like it's setup perfectly.

[grimsbylander]

I think you need to consider the type of fishing you do and the water you fish. If you're trolling 90% of the time or generally fishing small lakes, I'd seriously consider the 115 4 stroke. If you like to run all over Simcoe, out to the blue zone on lake O, or fish with a boat full of people, you can't go wrong with the added HP.

[Rustic-Fisher]

I was in the same situation, just different boats . Went with the 115CT , the rig flys with it . At over 20’ it’s rated for a 150, but given the light weight of the boat 115 was plenty , even the dealer advised against the 150 on modified V Jon boat.  Any other rig , i would of maxed out the Motor also . Only 8 hrs on the motor but man is it quiet and sips fuel.

 

 

[craigdritchie]

Whether to go 115 or 150 depends on what you're trying to achieve and what kind of hull you're screwing this thing onto. Things to consider:

• The 150 weighs nearly 100 pounds more that the 115 (455 pounds versus 359 lbs). Sure it has more power, but that much more weight on the transom means actual performance gains might not amount to much.
• The 150 costs more to buy than the 115.
• The 150 will cost more to operate than the 115. Both engines are inline fours, but the 150 uses a 3.0L block where the 115 is a 2.1L. The bigger block will use more fuel.
• The 150 has a much bigger alternator than the 115 (60 amps, vs 35 amps) so if you run a lot of electronics or spend most of your time moving a slow troll, that could be very important.

For what it's worth Merc's Command Thrust is designed to deliver more grunt for heavier, bulkier pontoon boats ... on a fishing boat that glides through the water pretty effortlessly, the extra traction is hardly noticeable (okay, it really isn't noticeable ... at all). The big benefit is that the larger diameter gear case spins a bigger prop (same props as the 150) so you have more selection to pick from.

Seriously? I'd go talk to your dealer. Terry is absolutely right, the hull you're putting this engine on makes more difference than anything else.

Edited July 9, 2018 by craigdritchie

[Old Ironmaker]

I'm not familiar with the "thrust feature until reading Craig's post, he knows his stuff . In a marine application in my opinion POWER always reigns supreme. Going to 150 Merc is a no brainer, I am a Merc guy. I don't believe 100 pounds makes enough difference not to power up. My kicker I put on the StarCraft weighs almost 100 pound, more with a full tank of fuel. I saw no measurable difference in top end speed or handling. I do agree hull design is a very important factor. Yes talk to a dealer, he will push what bring him  more $$ unless he's a good dealer. l

Blue if you are reading this per chance it took me 30 minutes to post this.

Johnny D

 

[hutch4113]

Ok.  Will have to see what they say.  I think the 150 still makes sense.  The 41 mph is at WOT.  If I can get that, but with fewer RPM's because of a larger motor, it might be a win.

The original boat test videos I watched for my boat all had 150's on it - and it was part of the build package too.  As such I would suspect it will handle it just fine.

Appreciate all the input -  giving me some things to think about.

[Old Ironmaker]

Huthch, how fast is fast enough?

Edited July 10, 2018 by Old Ironmaker

[hutch4113]

What can I say?  I feel the need........the need for speed.....?

[hutch4113]

I guess my other concern was, would the 115HP 4 Stroke, provide less performance than the 2 stroke it would replace.

[grimsbylander]

1 hour ago, hutch4113 said:

What can I say?  I feel the need........the need for speed.....?

You can always back off the throttle, I'd max out that hull without hesitation. 

The only reason I run a 200hp is because the spec plate doesn't say 300. lol 

[aplumma]

Consider the weight of the 4 stroke compared to your 2 stroke. I have a 1989 Ranger with a two stroke 150 and with all of the fuel, batteries 3 , charger and  person fishing on the back deck it is balanced. With another 150 lbs of 4 stroke 150 motor I could have a boat wake while docked wash into the boat if it is pointed nose inward. Just a though before you decide. I decided to rebuild Because of this fact so  my gt150 became a GTX 150 with SS tuned prop. I can hit 60 mph on the water it is almost fast enough. 

Art

[angelcanon]

AOk now for some rational thought, 115 or 150 going 2 stroke or 4, do you need to get a hole shot that sticks you to your seat, do you want dependability, etc theres a ton of arguments but 2 things stand out get the boat up outta to water and into trim, every motor is going to eventually plane, personally a little get up and go helps but after that things depend upon is it a cruiser fishing or water ski, or a little of everything. 

[Mister G]

First I would NOT just consider a Merc because the boat is wired for it. You want NEW controls and wiring with a new outboard and if you think you're saving money by keeping the old stuff you are wrong.

Take a look at other outboards, at least one is offering a 10 YEAR Warranty right now. Five years later you decide to sell that rig and the outboard has 5 years left on warranty is a GREAT selling feature.

[hutch4113]

I ended up switching brands.  Got a excellent price on a new 135 HO e-tec.  So going that route.  From what I can see these are pretty impressive motors - though I know there will be some haters out there.

Going to see if I can sell the Powerhead to my Optimax, which is in good shape.

[OhioFisherman]

It sounds good?